Require sRGB write control for sRGB support. Add flag to GrPaint to suppress linear -> sRGB convers…

src/gpu/GrYUVProvider.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrContext.h"
 #include "GrDrawContext.h"
 #include "GrYUVProvider.h"
@@ skipping 105 matching lines @@
     SkAutoTUnref<GrTexture> result(ctx->textureProvider()->createTexture(rtDesc, SkBudgeted::kYes,
                                                                          nullptr, 0));
     if (!result) {
         return nullptr;
     }
 
     GrRenderTarget* renderTarget = result->asRenderTarget();
     SkASSERT(renderTarget);
 
     GrPaint paint;
+    // We may be decoding an sRGB image, but the result of our linear math on the YUV planes
+    // is already in sRGB in that case. Don't convert (which will make the image too bright).
+    paint.setDisableOutputConversionToSRGB(true);
     SkAutoTUnref<const GrFragmentProcessor> yuvToRgbProcessor(
                                         GrYUVEffect::CreateYUVToRGB(yuvTextures[0],
                                                                     yuvTextures[1],
                                                                     yuvTextures[2],
                                                                     yuvInfo.fSizeInfo.fSizes,
                                                                     yuvInfo.fColorSpace));
     paint.addColorFragmentProcessor(yuvToRgbProcessor);
     paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
     const SkRect r = SkRect::MakeIWH(yuvInfo.fSizeInfo.fSizes[SkYUVSizeInfo::kY].fWidth,
             yuvInfo.fSizeInfo.fSizes[SkYUVSizeInfo::kY].fHeight);
 
     SkAutoTUnref<GrDrawContext> drawContext(ctx->drawContext(renderTarget));
     if (!drawContext) {
         return nullptr;
     }
 
     drawContext->drawRect(GrClip::WideOpen(), paint, SkMatrix::I(), r);
 
     return result.release();
 }